Darrell Vanterpool dresses like a lot of guys his age: low-slung skinny jeans, fitted hat, button-up shirt and a pair of skate shoes. He’s also black. “I’m 19 years old – two years older than Trayvon,” Vanterpool told Rolling Stone as he marched through the streets of New York on Sunday. “It could’ve been me.” He paused and said it again: “It could’ve been me.”

Vanterpool was just one of many across the country who gathered for peaceful protests the day after a Florida jury acquitted George Zimmerman of all charges in the killing of unarmed 17-year-old Trayvon Martin. Though he began the day with no intention of attending a protest, Vanterpool joined the thousands who took over the streets in New York City. Their march began in Union Square as dusk approached. Demonstrators stood among chalk outlines of human bodies sprinkled with Skittles – Martin was on a candy run when he was killed – before the procession began making its way north. Traffic came to a stop as demonstrators chanted, “The whole system’s guilty.” Cabbies stepped out of their cars to snap photos. Bystanders filmed with their cell phones, pumped their fists in the air and in many cases stopped what they were doing and joined the march.

A man with Martin’s name written on his cheeks carried a young boy on his shoulders. Together, they held a flattened cardboard box with a piece of notebook paper stuck to the front. In blue and red marker, the sign asked, “Will they shoot me too?”

The march ended under the bright lights of Times Square, where demonstrators sat and listened as speakers passed a megaphone. “This is 2013,” a man said, his voice amplified enough for the wide-eyed tourists on the periphery to hear. “We have plenty of peace, but no justice.”

President Barack Obama – who said last year that if he had a son, “he’d look like Trayvon” – made an appeal for calm in the wake of the verdict that came down late Saturday night. “The death of Trayvon Martin was a tragedy. Not just for his family, or for any one community, but for America,” said Obama. “I know this case has elicited strong passions. And in the wake of the verdict, I know those passions may be running even higher. But we are a nation of laws, and a jury has spoken. I now ask every American to respect the call for calm reflection from two parents who lost their young son.”

But in cities around the country, people took their outrage to the streets. In Los Angeles, protesters temporarily blocked a highway, carrying posters bearing a now-familiar image of Martin’s face with a hoodie pulled over his head. The LAPD issued a city-wide tactical alert and deployed cops in riot gear; the police claimed batteries and bottles were thrown at officers and responded by firing non-lethal rounds. Six people were arrested at an “unlawful assembly” in Hollywood’s CNN building. In Oakland, fires were set in garbage bins. Following the peaceful gathering in Times Square, the NYPD arrested 12 people on a splinter march bound for Harlem.

But despite the raw emotions involved, the vast majority of the demonstrators – in San Francisco, Boston, Detroit, Chicago, Washington, D.C., Milwaukee, Atlanta, Philadelphia, Miami and even Sanford, Florida, where Martin was killed – were overwhelmingly peaceful.

Protesters were not alone in speaking their minds about the verdict. At a Nashville concert, Beyonce called for a moment of silence “for Trayvon.” Early Sunday morning, Young Jeezy uploaded a new track – “It’s a Cold World (A Tribute to Trayvon Martin)” – to honor the dead teen. At a Q&A on Saturday night, Michael B. Jordan, star of the acclaimed new film Fruitvale Station – which tells the story of Oakland’s Oscar Grant, an unarmed black man killed by a white cop in 2009 – said, “My heart hurts so bad right now. I wasn’t going to come after I found out about George Zimmerman getting acquitted. It broke me up.”

On Sunday, Zimmerman’s lawyer told the press there’s no question his client will retrieve the pistol he used to shoot Martin through the heart – because he needs it now “even more.” With no apparent sense of irony, Zimmerman’s brother Robert said, “There are people that would want to take the law into their own hands as they perceive it, or be vigilantes in some sense. They think that justice was not served, they won’t respect the verdict no matter how it was reached and they will always present a threat to George and his family.”

For young men like Vanterpool, the fear of being killed for the way they look is nothing new. “Some people think, ‘Oh, it shouldn’t be about race,'” he said. “When a person is profiled as doing something suspicious for walking in a hoodie on a rainy day, that’s racial profiling.”

“It is scary,” Vanterpool added. “[Martin] went to the store, bought Skittles and a watermelon Arizona and was shot on his way back. Many times I go out at night just to get a snack, cause I’m hungry.” Vanterpool believes circumstances would have been very different if Martin were white and Zimmerman was a black man. “At the end of the day, if it was a black 29-year-old that had shot a white 17-year-old, I feel like he would’ve been in jail.”

As the sun began to set in New York on Sunday, Woods Legrand, a 20-year-old black man from Flatbush, Brooklyn, walked arm-in-arm with his friends at the head of the march. Their anger and frustration was palpable as they led chants and directed the crowd.

“I was hurt,” Legrand told Rolling Stone of his feelings when he heard the verdict. “But it wasn’t nothing new to me. I just took it in stride, and I hope this can serve as a catalyst.”

A catalyst for what? “A revolt,” he added. “I’m not an activist. I’m not a freedom fighter. I’m not a firefly or a revolutionary. I’m just a kid, man, with an opinion. And this shit is fucked up.”